Caption: Trypanosome. Coloured scanning electron micro- graph (SEM) of a parasitic Trypanosoma brucei protozoan. T. brucei is the cause of African sleeping sickness (trypanosomiasis) in humans. The ribbon-like T. brucei are carried in the saliva of the blood-drinking tsetse fly. The protozoa enter a human host through the wound made by the fly when it feeds. The protozoa infect the blood, lymph and spinal fluid, and begin to divide. Damage to the nervous system by the infection eventually leads to lethargy, tremors, and mental and physical deterioration. The sufferer finally enters a comatose state and dies. Magnification: x6,250 at 6x4.5cm size.